The Experts below are selected from a list of 102 Experts worldwide ranked by ideXlab platform
Enrique Luengo - One of the best experts on this subject based on the ideXlab platform.
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Distribution and effectiveness of Nivation in Mediterranean mountains: Peñalara (Spain)
Geomorphology, 2002Co-Authors: David Palacios, Nuria Andrés, Enrique LuengoAbstract:Abstract Snow accumulation is responsible for geomorphic and biogeographic processes taking place in the southern sector of the Penalara massif in central Spain (40°51′N, 3°57′W; max. altitude 2428 m at Pico de Penalara). This work compares the intensity of Nivation on the eastern slope, leeward of the prevailing westerly winds and heavily eroded by glacial activity during the Pleistocene, to that of the western slope on the windward side, unaffected by glacial erosion and completely covered by a thick weathering mantle. On the eastern slope, Nivation is effective only where the weathering mantle is exposed or on morainic formations. It does not occur on the landforms derived from glacial erosion. In contrast, the western side shows almost no evidence of snow action except where catastrophic mass movements have altered the regularity of the slope. During the post-glacial epoch, Nivation cirques formed in the scars left by mass wasting. In the last 30 years, spring temperatures have increased and this activity has diminished. The pattern of evolution observed at Penalara can be extrapolated to other Mediterranean mountains with similar characteristics such as marginal glacial activity during the Pleistocene, unconsolidated formations on the summits caused by chemical weathering, and dry, hot summers that can increase the effectiveness of Nivation.
Jaroš Obu - One of the best experts on this subject based on the ideXlab platform.
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Periglacial and glacial landforms in western part of Pohorje Mountains
Dela, 2011Co-Authors: Jaroš ObuAbstract:Recent geomorphological research in eastern part of Pohorje Mountains has revealed new information about periglacial and glacial landforms of that area. Based on these findings, similar landforms in western part of Pohorje were studied, especially cryoplanation terraces and Nivation hollows. Field research has also revealed the existence of ploughing rocks, blockstreams, blockfields and one cirque.
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Periglacialne in ledeniške oblike v zahodnem delu Pohorja = Periglacial and glacial landforms in western part of Pohorje mountains
Znanstvena založba Filozofske fakultete Univerze v Ljubljani (Ljubljana University Press Faculty of Arts), 2011Co-Authors: Jaroš ObuAbstract:Recent geomorphological research in eastern part of Pohorje Mountains has revealednew information about periglacial and glacial landforms of that area. Based on thesefindings, similar landforms in western part of Pohorje were studied, especially cryoplanationterraces and Nivation hollows. Field research has also revealed the existence ofploughing rocks, blockstreams, blockfields and one cirque
David Palacios - One of the best experts on this subject based on the ideXlab platform.
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Distribution and effectiveness of Nivation in Mediterranean mountains: Peñalara (Spain)
Geomorphology, 2002Co-Authors: David Palacios, Nuria Andrés, Enrique LuengoAbstract:Abstract Snow accumulation is responsible for geomorphic and biogeographic processes taking place in the southern sector of the Penalara massif in central Spain (40°51′N, 3°57′W; max. altitude 2428 m at Pico de Penalara). This work compares the intensity of Nivation on the eastern slope, leeward of the prevailing westerly winds and heavily eroded by glacial activity during the Pleistocene, to that of the western slope on the windward side, unaffected by glacial erosion and completely covered by a thick weathering mantle. On the eastern slope, Nivation is effective only where the weathering mantle is exposed or on morainic formations. It does not occur on the landforms derived from glacial erosion. In contrast, the western side shows almost no evidence of snow action except where catastrophic mass movements have altered the regularity of the slope. During the post-glacial epoch, Nivation cirques formed in the scars left by mass wasting. In the last 30 years, spring temperatures have increased and this activity has diminished. The pattern of evolution observed at Penalara can be extrapolated to other Mediterranean mountains with similar characteristics such as marginal glacial activity during the Pleistocene, unconsolidated formations on the summits caused by chemical weathering, and dry, hot summers that can increase the effectiveness of Nivation.
Nuria Andrés - One of the best experts on this subject based on the ideXlab platform.
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Distribution and effectiveness of Nivation in Mediterranean mountains: Peñalara (Spain)
Geomorphology, 2002Co-Authors: David Palacios, Nuria Andrés, Enrique LuengoAbstract:Abstract Snow accumulation is responsible for geomorphic and biogeographic processes taking place in the southern sector of the Penalara massif in central Spain (40°51′N, 3°57′W; max. altitude 2428 m at Pico de Penalara). This work compares the intensity of Nivation on the eastern slope, leeward of the prevailing westerly winds and heavily eroded by glacial activity during the Pleistocene, to that of the western slope on the windward side, unaffected by glacial erosion and completely covered by a thick weathering mantle. On the eastern slope, Nivation is effective only where the weathering mantle is exposed or on morainic formations. It does not occur on the landforms derived from glacial erosion. In contrast, the western side shows almost no evidence of snow action except where catastrophic mass movements have altered the regularity of the slope. During the post-glacial epoch, Nivation cirques formed in the scars left by mass wasting. In the last 30 years, spring temperatures have increased and this activity has diminished. The pattern of evolution observed at Penalara can be extrapolated to other Mediterranean mountains with similar characteristics such as marginal glacial activity during the Pleistocene, unconsolidated formations on the summits caused by chemical weathering, and dry, hot summers that can increase the effectiveness of Nivation.
Kevin Hall - One of the best experts on this subject based on the ideXlab platform.
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Nivation and cryoplanation: the case for scrutiny and integration
Progress in Physical Geography: Earth and Environment, 2002Co-Authors: Colin E. Thorn, Kevin HallAbstract:Nivation and cryoplanation are deeply entrenched and widely invoked morphogenet- ic concepts within periglacial geomorphology. However, given their complexity and purported significance in landform development, neither has received the scientific scrutiny merited. Nivation is generally associated with the weathering and mass movement processes stemming from late-lying seasonal snow and the ensuing landforms. As a process suite it invokes mechanisms such as freeze-thaw weathering and solifluction. Cryoplanation also invokes a process suite, but one that also embraces Nivation. Research in the last two or three decades has begun to provide a much sharper definition of Nivation, but the available information is still inadequate for a central mechanism in periglacial landscapes. Cryoplanation is used to explain some benches, terraces and pediments that appear to be widespread in some periglacial envi- ronments: however, substantive field research on the mechanisms involved is all but absent. A case is presented for viewing Nivation and cryoplanation as a single process spectrum much in need of state-of-the-art research.
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Nivation or cryoplanation: Different terms, same features?
Polar Geography, 1998Co-Authors: Kevin HallAbstract:Abstract Nivation and cryoplanation are considered to produce separate landforms—hence their distinct names. However, despite this duality of terms, both utilize the same basic processes. A review of the literature indicates confusion and overlap regarding Nivation and cryoplanation and their meaning. First, Nivation is clearly described in its literature as exploiting pre‐existing hollows. Thus Nivation cannot be the initiator of cryoplanation as is frequently suggested in the cryoplanation literature. Second, Nivation requires snow, usually in some quantity, which must experience melt, whereas cryoplanation is said to characterize arid or semiarid regions. Third, many authors associate cryoplanation with permafrost, whereas this association has never been the case with Nivation. Fourth, if both utilize the same basic suite of processes, what then justifies this terminological dichotomy? It is here argued that ‘Nivation’ and ‘cryoplanation’ are two end members of the same feature/process suite.